PALO ALTO, Calif. -- A terminally ill cancer patient has been arrested and charged with attempted murder after he traveled to the San Francisco Bay Area to kill three doctors who had treated him, authorities said Tuesday.

The Palo Alto Police Department said 58-year-old Yue Chen of Visalia had rented a car and traveled to the Bay Area with plans to kill his three doctors because he was upset about his treatment.

On Wednesday, May 31, the Visalia Police Department told the Palo Alto Police Department they were looking for Chen. They said he was missing along with his two legally owned handguns. Visalia police told PAPD they had learned Chen was driving to the Bay Area with the intent to shoot the three doctors at their homes.

Just before 8 p.m., California Highway Patrol in San Jose saw the suspect's rental car and pulled him over. Officers say they found two loaded semi-automatic handguns with high-capacity magazines.

Highway Patrol officers arrested Chen and took him to the hospital to get treatment for his medical condition. Once he was discharged, Palo Alto police booked him on three charges of attempted murder and carrying a loaded firearm.

Palo Alto Police say 58-year-old Yue Chen was a stage 4 cancer patient who drove more than 200 miles from Visalia to the Bay Area to murder at least 3 local doctors who had treated him more than a year ago.

Palo Alto police say Chen was a Stage IV cancer patient who drove more than 200 miles from Visalia to the Bay Area to murder at least three doctors who had treated him more than a year ago.

Chen's wife contacted Visalia police after Chen took off, leaving a note behind that said, "If today I do not kill them, their sins will continue."

CHP officers stopped Chen on Southbound 101.

"As many stops as we make, we don't know where our interdiction may have stopped a crime or saved a life in this situation we knew," said CHP Officer Ross Lee.

In Chen's rental car, they discovered a notebook with the names and home addresses of doctors, a face mask and the two handguns registered to him.

"They did have extended capacity magazines which were illegal, the guns were loaded, one of those guns had 30 rounds of ammunition in it, the other had 16 rounds of ammunition and as I say they were within arms reach of him," said Lt. Reifschneider. Investigators also recovered a note titled "Why do I Kill" with the reasons "revenge" and "this is the possible result if you treat people as an animal."

Chen is being held at Santa Clara County Main Jail.

While the complaint names the three doctors, the Santa Clara County District Attorney's Office asked ABC7 News not to release their names out of safety concerns. Palo Alto police say they believe more than three doctors were potentially at risk last week.

Chen, who also planned to kill himself, was angry the doctors had treated him like a "laboratory monkey," according to the suicide note found by police, the Mercury News reported (http://bayareane.ws/2sBQfLO).

Chen failed to find any of the doctors, got lost and may have been on his way back home when he was arrested in San Jose, the Palo Alto Police Department said.

The names of the hospitals were redacted in the police report, but prosecutors said one of the doctors worked at UCSF Medical Center. Another UCSF physician and at least one Stanford Health Care doctor also were targeted, the report said.

After his arrest, Chen told detectives he believes he was being used for research purposes.

"They only hurt me," Chen reportedly told detectives. "They hurt me both hospitals. They really screw my life, or the doctors lie to me. Hospitals, they all cover for each other."